Veni, Vidi, VISA

Serendipity 1.5.3 has been released, as a security-fix release with no other relevant changes.

A security issue has been discovered by Stefan Esser (http://www.sektioneins.com/index/index.html) during the course of the Month of PHP Security (http://www.php-security.org/). This issue was found in the WYSIWYG-Library Xinha (http://trac.xinha.org/) (that Serendipity uses), and affects certain plugins to Xinha (Linker, ImageManager, ExtendedFileManager, InsertSnippet) which can use a dynamic configuration loader. This loader allows to upload file with arbitrary PHP-Code and thus allows remote code execution, even when not logged in to the Xinha/Serendipity backend.

Due to the seriousness of this bug, we urge everyone to upgrade their installations. People who don't want the hassle of a full upgrade and are not using the mentioned Xinha-plugins actively, can simply delete the file htmlarea/contrib/php-xinha.php, which will render the mentioned plugins and exploits useless.

Thanks to Stefan Esser for reporting this issue to us, and making a quick bugfix possible.